Valmiki Ramayana Bala Kanda Sarga 4 Shloka 21
Original Shlokaआश्चर्यमिदमाख्यानं मुनिना सम्प्रकीर्तितम्। परं कवीनामाधारं समाप्तं च यथाक्रमम्।।1.4.21।।
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मुनिना by sage Valmiki, सम्प्रकीर्तितम् has been told, इदम् this, आख्यानम् legendary poem, आश्चर्यम् is causing surprise, कवीनाम् for the poets, परम् supreme, आधारम् foundation, यथाक्रमम् according to specific rules and order, समाप्तं च is also completed.
This wonderful epic chronologically composed and completed by the sage (Valmiki), is the supreme source for poetry.